Cognitive psychology is a branched field that encompasses learning, memory, perception, attention.... and though among others (though among others what?). The most prominent key figures related to this field were Wilhelm Wundt, Max Wertheimer, Wolfgang Kohler, Anne Treisman, Hermann Von Helmholtz, and Irving Biederman whose findings, works, and effort are of extreme importance to understanding the fields of perception and attention. Some of their discoveries and work lead to the cognitive revolution and the others contributed many breakthroughs that stretched the very range of understanding in cognitive psychology that we are now at today. Some of them would never know the later importance of their findings and some findings were left behind. For instance, Wundt dies in 1920 leaving the basis of what makes the field of cognitive psychology today such as the experimental method.
Another example is introspection, or the participant's description of a sensation, in other words self evaluation (Clandrum, 2012). This was criticized for being inaccurate, but due to this criticism psychology evolved into a more experimental and objective science (Cyprus, 2012). But without a doubt, the field of cognitive psychology and our understanding of perception and attention would not be what it is today if it were not for these very founders that...(some kind of awesome conclusion they did goes here)-- I'll edit more as we go along of course.

--Andrea Russo and Dillon B